The proposed study will use an innovative social neuroscience method to examine brain activity associated with error detection among schizophrenia patients while they observe another individual performing a task. The ability to rapidly and accurately interpret other people's actions is essential to appropriate interpersonal interactions and failure to do so might underlie the pervasive social deficits that many schizophrenia patients experience. Previous studies have identified a component of the event-related brain potential (ERP) known as the error-related negativity (ERN) that is elicited when people make incorrect responses and is thought to reflect the activity of a generic response monitoring system. In psychiatrically healthy people, the ERN is also elicited during observation of others making incorrect responses. The ERN has been shown to be attenuated in schizophrenia patients following the execution of errors but this will be the first study to examine the ERN in a social context in schizophrenia. The specific aims of the project are 1) to examine whether ERN abnormalities that are present during task performance will also be present when schizophrenia patients observe another individual make errors, 2) to determine whether any abnormalities are specific to ERN by comparing the ERN during observation to brain activity that occurs in the anticipation of a observed or executed motor response (the lateralized readiness potential, or LRP), and 3) to explore the relationship between ERN amplitude and the symptoms of schizophrenia and ratings of community social functioning. There will be two groups of participants, individuals with a diagnosis of schizophrenia and psychiatrically healthy comparison subjects. Brain activity (electroencephalography) will be recorded while participants complete a choice reaction time task (the flanker task) and while observing a confederate complete the task so that activity preceding and following correct and incorrect responses during execution and observation can be compared in the two groups of participants. Completion of this study and the accompanying training activities will support the applicant's long-term goal of furthering the scientific understanding of the interaction of physiological and social factors in schizophrenia where these deficits have been implicated not only in the expression of symptomatology but also in etiology. The proposed study may improve the understanding of the complex deficit in social functioning in schizophrenia, ultimately leading to better definitions of the specific nature of this impairment, informing the development of more effective interventions for reducing social impairment in schizophrenia patients, thus increasing and improving their participation in the community. [unreadable] [unreadable] [unreadable]